qApp: fix flag handling in Python 3.8+ and a Python 3.9 issue

This is an old problem that was solved for Python 2.7.
From Python 3.8 on, the behavior is the same with Python 3.

The fix finally was to extend a Python 2.7 patch to Python 3
as well. See the Jira issue for details.

This patch includes also a small patch that was mentioned as
necessary for Python 3.9: Python issue 40217. I have seen no
effect of this change yet but applied the patch, anyway.

Origin: https://codereview.qt-project.org/c/pyside/pyside-setup/+/328046

Gbp-Pq: Name qApp-fix-flag-handling.patch

diff --git a/sources/shiboken2/libshiboken/basewrapper.cpp b/sources/shiboken2/libshiboken/basewrapper.cpp
index d866d133c1ca741f1e4909dfe1025c8994fc7a92..b38fb3a5aceef9c068d8cda0aa1edb21fb9fef9b 100644 (file)
--- a/sources/shiboken2/libshiboken/basewrapper.cpp
+++ b/sources/shiboken2/libshiboken/basewrapper.cpp
@@ -319,6 +319,11 @@ static int SbkObject_traverse(PyObject *self, visitproc visit, void *arg)
 
     if (sbkSelf->ob_dict)
         Py_VISIT(sbkSelf->ob_dict);
+
+#if PY_VERSION_HEX >= 0x03090000
+    // This was not needed before Python 3.9 (Python issue 35810 and 40217)
+    Py_VISIT(Py_TYPE(self));
+#endif
     return 0;
 }
 
@@ -769,12 +774,15 @@ PyObject *SbkQAppTpNew(PyTypeObject *subtype, PyObject *, PyObject *)
     // PYSIDE-560:
     // We avoid to use this in Python 3, because we have a hard time to get
     // write access to these flags
-#ifndef IS_PY3K
+
+    // PYSIDE-1447:
+    // Since Python 3.8, we have the same weird flags handling in Python 3.8
+    // as well. The singleton Python is no longer needed and we could remove
+    // the whole special handling, maybe in another checkin.
     if (PyType_HasFeature(subtype, Py_TPFLAGS_HAVE_GC)) {
         subtype->tp_flags &= ~Py_TPFLAGS_HAVE_GC;
         subtype->tp_free = PyObject_Del;
     }
-#endif
     auto self = reinterpret_cast<SbkObject *>(MakeQAppWrapper(subtype));
     return self == nullptr ? nullptr : _setupNew(self, subtype);
 }